All machines used for packaging, and also many processing machines, require the products to be packaged (or the intermediate products on which appropriate processes are to be performed) to comply with specific rules of motion which can provide for portions at constant speed, accelerations, decelerations and stops, which are variously spaced as a function of the requirements of the specific step of processing to which they are subjected.
In order to deal with complex rules of motion, specific controlled motor drives are normally used.
Generally, in order to ensure that each one of the elements of a carousel or of a line for packaging/processing can move independently of the contiguous ones but in accordance with the specific rule of motion, it is normal to resort to specific controlled motor drive units, which are controlled by a respective control and management processor.
This solution offers excellent versatility and allows to comply perfectly with the parameters prescribed by the rule of motion of each individual element.
However, the presence of many individually controlled motor drive units entails a considerable increase in production costs (tied to the purchase costs of the individual units) and also the need to have a computer that is capable of managing independently the supply parameters of each individual unit.
These machines are therefore extremely expensive.
Moreover, the increase in costs, in many cases, cannot be justified in relation to the fact that the various rules of motion of each movable element will remain unchanged throughout the operating life of the machine
The reconfiguration possibility that is typical of controlled motor drive units, therefore, in many cases is not utilized fully and validly.
This entails that machines of the known type, in order to cope with the need to move each element according to a specific, predefined and complex rule of motion, resort to controlled movement units which are controlled by a respective computer, despite not providing for possible modifications of said rules of motion, with consequent high production costs.
It is also known to resort to machines the movable elements of which are all mounted on respective conveyance elements that trace the steps of a common rule of motion.
Obviously, in this manner it is not possible to operate continuously, and each stop affects all the elements, greatly limiting the speed of machine and minimizing its productivity.